1. Field of the Invention
The present invention generally relates to a particulate metering and alignment apparatus. In particular, the present invention relates to a particulate metering and alignment apparatus, comprising a product feeder and a vibrating bed feeder, which may be used to provide a substantially uniform flow of particulates for distribution onto a flow of substrate.
2. Related Background Art
A wide variety of equipment is known for transporting and/or metering particulate material, such as, e.g., food products, coal and other mineral material, and dry goods handled in solid particulate form. When used to coat a flow of a substrate with particulate material, transport or metering equipment must provide a uniform flow of tightly nested particulates without particulate bridging to provide a uniform coating on the substrate.
Known transport and metering systems require two or more pieces of equipment to feed and provide the desired flow of particulates. The use of multiple devices increases the space required for the transport and metering systems, as well as the capital costs. Therefore, a need exists for a particulate metering and alignment apparatus that combines the metering and transport functions in a single, smaller device, and provides at least one stream of tightly nested flow of particulates. No device, known at the time of the present invention, combines metering, distribution, and streaming of particulates. The present invention provides such a device.
The present invention is directed to a particulate metering and alignment apparatus and to a method of producing a plurality of parallel streams of nested particulates for distribution onto a substrate at a desired discharge rate using the apparatus of the invention. The apparatus of the invention comprises a product feeder in functional communication with a vibrating bed feeder, and at least one tubular nozzle. The at least one nozzle is configured to discharge product from the product feeder onto the vibrating bed feeder at a desired product discharge rate, and has a variable angle of tilt relative to the vibrating bed feeder, where the at least one nozzle is configured such that the product discharge rate varies as the angle of tilt of the at least one nozzle is varied, and there is at least one angle of tilt at which no product is discharged.
The product feeder is preferably a loss-in-weight feeder, and preferably further comprises a hollow hopper, defining a product feeder discharge outlet and an interior volume for storing product to be metered and aligned. The at least one nozzle an inlet in functional communication with the product feeder discharge outlet and an outlet or orifice proximate to a product distribution zone of a vibrating bed feeder tray, where the at least one nozzle is positioned such that product discharged from the at least one nozzle outlet or orifice is deposited onto the product distribution zone of the vibrating bed feeder tray.
The method of the invention comprises the steps of placing particulate material of a given weight into a feeder hopper of a product feeder, discharging the particulate material from the hopper through at least one nozzle onto a vibrating bed feeder at a discharge rate determined by the angle of tilt of the nozzle, in conjunction with the vibrational frequency and amplitude of the vibrating bed feeder, adjusting the angle of tilt to obtain the desired discharge rate, forming a plurality of parallel streams of the particulate material on the vibrating bed feeder, and distributing the particulate material from the vibrating bed feeder onto a substrate.
Preferably, the method further comprises the steps of continuously monitoring the change in the weight of the particulate matter in the hopper as the particulate matter is discharged, determining the discharge rate from the change in weight, determining any change in the discharge rate, and adjusting the angle of tilt of the at least one nozzle to maintain the desired discharge rate.
The parallel streams may be formed by discharging the product from the at least one nozzle onto a product distribution zone of the vibrating bed feeder, and transporting the product on the distribution zone into a plurality of channels on the vibrating bed feeder. Preferably, the particulate matter is directed from the product distribution zone to the channels with one or more flow diverters or channel funnels, and the flow of the particulates in the channels is restricted to maintain a nested flow and/or is guided onto a substrate by a discharge guide at the discharge end of each product channel.